Omio (until a few weeks ago GoEuro) wants to help you compare bus, train and flight connections and cooperates with Deutsche Bahn, Flixbus and other transport providers. So you can buy tickets for the same price via Omio as you would pay on Bahn.de, for example.
Omio has now started a refer-a-friend scheme so that you and your friends can both benefit! If you are invited to Omio or invite a friend and they make a booking, you will be credited 10€ to your account which you can redeem on a booking of at least 40€:
The coupon can even be used to book flights by e.g. Ryanair, Easyjet or Eurowings. However, there is a booking fee of 3-4% (which is only indicated after the passenger data has been entered… whether this is legal or not is questionable..). Still a good discount compared to booking directly with the airline.
Unfortunately, Flixbus bs tickets cannot be purchased with the coupon. You will be forwarded directly from Omio to Flixbus where the coupon is not valid.
You can redeem a coupon code at the end of the booking process. Next to Use a discount you have to click on the arrow and the coupon field will open:
After clicking on Apply, the value of the discount will immediately be subtracted from the total if the coupon code is valid.